1681386 has 64 divisors (see below), whose sum is σ = 4224000. Its totient is φ = 444528.

The previous prime is 1681363. The next prime is 1681397. The reversal of 1681386 is 6831861.

1681386 = 1² + 2² + ... + 171².

1681386 is a modest number, since divided by 1386 gives 168 as remainder.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 39081 + ... + 39123.

It is an arithmetic number, because the mean of its divisors is an integer number (66000).

2^1681386 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1681386, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2112000).

1681386 is an abundant number, since it is smaller than the sum of its proper divisors (2542614).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1681386 is a wasteful number, since it uses less digits than its factorization.

1681386 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88 (or 74 counting only the distinct ones).

The product of its digits is 6912, while the sum is 33.

The square root of 1681386 is about 1296.6826905608. The cubic root of 1681386 is about 118.9111216399.

The spelling of 1681386 in words is "one million, six hundred eighty-one thousand, three hundred eighty-six".